Pumps are used in various applications. In vehicles, fuel pumps are used to move fuel from the vehicle tank (or other storage areas) to the engine (or other destinations) where the fuel is ignited to operate the engine (or otherwise used). In one particular application that is realized in vehicles, high pressure pumps are used in vehicles to move fuel into the fuel injection system of the engine.
For multi-level or multi-fuel system engines, current high pressure fuel pumps that are utilized and these pumps operate continuously. That is, the pumps are operated regardless of whether there is fuel flowing through the pump or no fuel is flowing through the pump. Unfortunately, when the pump is operated without fuel flow, there is wearing of the moving components of the pump and exposure to high temperature that can lead to pump failure. In other words, the pump continues to operate during engine operation, even though the pump is not being used to provide a pressure into the fuel injection system.
Some current approaches place some fluid in the pump to provide lubrication for the pump components. However, these approaches waste valuable energy and are otherwise complicated, inefficient, and/or costly to accomplish.
Consequently, current approaches either have not addressed these problems or have their own limitations. As a result, some user dissatisfaction has resulted from current approaches.
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